The function of ENSG00000143819 (EPHX1, epoxide hydrolase 1) is as follows. Biotransformation enzyme that catalyzes the hydrolysis of arene and aliphatic epoxides to less reactive and more water soluble dihydrodiols by the trans addition of water (By similarity). Plays a role in the metabolism of endogenous lipids such as epoxide-containing fatty acids (PubMed:22798687). Metabolizes the abundant endocannabinoid 2-arachidonoylglycerol (2-AG) to free arachidonic acid (AA) and glycerol (PubMed:24958911). Binds 20(S)-hydroxycholesterol (20(S)-OHC) (By similarity). {ECO:0000250|UniProtKB:P07687, ECO:0000250|UniProtKB:Q9D379, ECO:0000269|PubMed:22798687, ECO:0000269|PubMed:24958911}.